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Chinese Journal of Polymer Science 2024年第1期42卷 125-132,I0011页

作者： chang-Sheng Zuo Kang wang Li-zhen Sun Ting-Ting Sun Department of Physics Zhejiang University of Science and TechnologyHangzhou 310023China Department of Applied Physics Zhejiang University of TechnologyHangzhou 310014China

The polymer translocation through a nanopore from a donor space(or named cis side) to a receiver space(trans side) in the chaperone-induced crowded environment has attracted increasing attention in recent years due to its significance in biological systems and technological applications. In this work, we mainly focus on the effects of chaperone concentration and chaperone-polymer interaction on the polymer translocation. By assuming the polymer translocation to be a quasi-equilibrium process, the free energy F of the polymer can be estimated by Rosenbluth-Rosenbluth method and then the translocation time τ can be calculated by Fokker-Plank equation based on the obtained free energy landscape. Our calculation results show that the translocation time can be controlled by independently tuning the chaperone concentration and chaperone-polymer interaction at the cis side or the trans side. There exists a critical chaperone-polymer attraction ε~*=-0.2 at which the volume exclusion and interaction effects of the chaperone can balance each other. Additionally, we also find that at large chaperone-polymer attraction, the translocation time is mainly governed by the diffusion coefficient of the polymer.

关键词： Polymer translocation Rosenbluth-Rosenbluth method Fokker-Plank equation Free energy landscapes

Noninvasive Characterization of Metabolic changes in Ischemic Stroke Using Z-spectrum-fitted Multiparametric Chemical Exchange Saturation Transfer-weighted Magnetic Resonance Imaging

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Current Medical Science 2023年第5期43卷 970-978页

作者： zhen-xiong wang Xin-hua WEI Ke-jia CAI Wen-zhen ZHU chang-liang SU Department of Radiology Guangzhou First People’s HospitalSchool of MedicineSouth China University of TechnologyGuangzhou 510180China Department of Radiology Department of Bioengineeringand The Center for MR ResearchUniversity of Illinois at ChicagoChicago 60612USA Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Radiology Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhou 510060China

Objective This study aimed to noninvasively characterize the metabolic alterations in ischemic brain tissues using Z-spectrum-fitted multiparametric chemical exchange saturation transfer-weighted magnetic resonance imaging(CEST-MRI).Methods Three sets of Z-spectrum data with saturation power(B_(1))values of 1.5,2.5,and 3.5µT,respectively,were acquired from 17 patients with ischemic stroke.Multiple contrasts contributing to the Z-spectrum,including fitted amide proton transfer(APT_(fitted)),+2 ppm peak(CEST@2ppm),concomitantly fitted APT_(fitted) and CEST@2ppm(APT&CEST@2ppm),semisolid magnetization transfer contrast(MT),aliphatic nuclear Overhauser effect(NOE),and direct saturation of water(DSW),were fitted with 4 and 5 Lorentzian functions,respectively.The CEST metrics were compared between ischemic lesions and contralateral normal white matter(CNWM),and the correlation between the CEST metrics and the apparent diffusion coefficient(ADC)was assessed.The differences in the Z-spectrum metrics under varied B1 values were also investigated.Results Ischemic lesions showed increased APTfitted,CEST@2ppm,APT&CEST@2ppm,NOE,and DSW as well as decreased MT.APT&CEST@2ppm,MT,and DSW showed a significant correlation with ADC[APT&CEST@2ppm at the 3 B_(1) values:R=0.584/0.467/0.551;MT at the 3 B_(1) values:R=−0.717/−0.695/−0.762(4-parameter fitting),R=−0.734/−0.711/−0.785(5-parameter fitting);DSW of 4-/5-parameter fitting:R=0.794/0.811(2.5µT),R=0.800/0.790(3.5µT)].However,the asymmetric analysis of amide proton transfer(APT_(asym))could not differentiate the lesions from CNWM and showed no correlation with ADC.Furthermore,the Z-spectrum contrasts varied with B_(1).Conclusion The Z-spectrum-fitted multiparametric CEST-MRI can comprehensively detect metabolic alterations in ischemic brain tissues.

关键词： chemical exchange saturation transfer Z-spectrum ischemic stroke

新四环素耐药基因tet(63)的发现与鉴定

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中国预防兽医学报 2021年第1期43卷 112-112页

作者： ZHU YAO wang chang-zhen SCHWARZ STEFAN State Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research Institute Chinese Academy of Agricultural Sciences Harbin 150069 China. Institute of Microbiology and Epizootics Centre for Infection Medicine Department of Veterinary Medicine Freie Universität Berlin Berlin Germany.

四环素类抗生素因其广谱的抗菌活性、低生产成本以及无严重的不良反应被广泛应用于人医临床和畜牧养殖业。然而,随着四环素类抗生素的大量、不合理使用导致细菌四环素耐药性愈发严重,给人类和动物健康造成了巨大威胁。四环素耐药基因的... 详细信息

四环素类抗生素因其广谱的抗菌活性、低生产成本以及无严重的不良反应被广泛应用于人医临床和畜牧养殖业。然而,随着四环素类抗生素的大量、不合理使用导致细菌四环素耐药性愈发严重,给人类和动物健康造成了巨大威胁。四环素耐药基因的获得是细菌产生四环素类抗生素耐药性的最主要原因。同时,在持续的抗生素选择压力下,四环素耐药基因不断的产生和进化。

关键词：四环素耐药基因畜牧养殖业动物健康四环素类抗生素四环素耐药性抗菌活性抗生素选择生产成本

Polymer Translocation

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Chinese Journal of Polymer Science 2023年第5期41卷 683-698,I0007页

作者： Lu-Wei Lu zhen-Hua wang An-chang Shi Yu-Yuan Lu Li-Jia An State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China Department of Physics and Astronomy McMaster UniversityHamiltonOntario L8S4M1Canada

The translocation of a polymer through a pore that is much smaller than its size is a fundamental and actively researched topic in polymer physics.An understanding of the principles governing polymer translocation provides important guidance for various practical applications,such as the separation and purification of polymers,nanopore-based single-molecule deoxyribonucleic acid/ribonucleic acid(DNA/RNA)sequencing,transmembrane transport of DNA or RNA,and infection of bacterial cells by bacteriophages.The past several decades have seen great progresses on the study of polymer translocation.Here we present an overview of theoretical,experimental,and simulational stduies on polymer translocation,focusing on the roles played by several important factors,including initial polymer conformations,external fields,polymer topology and architectures,and confinement degree.We highlight the physical mechanisms of different types of polymer translocations,and the main controversies about the basic rules of translocation dynamics.We compare and contrast the behaviors of force-induced versus flow-induced translocations and the effects of unknotted versus knotted polymers.Finally,we mention several opportunities and challenges in the study of polymer translocation.

关键词： Polymer translocation Knotted polymers Translocation time Critical flux

Role of serum cystatin C in the prediction of contrast-induced nephropathy after intra-arterial interventions

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Chinese Medical Journal 2020年第4期133卷 408-414页

作者： zheng-Yu wang Yong-Li wang Jian Wei Long Jin zhen-chang wang Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Interventional Radiology The Sixth People's Hospital South CampusShanghai Jiao Tong UniversityShanghai 201499China

Background:The diagnosis of contrast-induced nephropathy(CIN)is usually based on changes in serum creatinine(sCr).However,sCr has poor sensitivity as a biomarker of kidney injury.The aim of this study was to investigate the usefulness of serum cystatin C(sCysC)to predict CIN after intra-arterial interventions.Methods:A total of 360 consecutive patients underwent intra-arterial procedures using digital subtraction angiography.SCr,sCysC,and estimated glomerular filtration rate were measured at 1 to 2 days before and at 48,72 h,and 7 days after the procedure.Results:Thirty-one patients(8.61%)developed CIN.Receiver operating characteristic(ROC)curve analysis showed that preoperative sCysC levels had good discriminatory power(area under the curve[AUC]=0.634;95%confidence interval[CI]=0.526-0.743)for evaluating the risk of CIN after an endovascular procedure,with a sensitivity of 53.33%and specificity of 73.70%.ROC analysis showed that sCysC at 48 h after contrast medium administration was predictive of CIN after an endovascular procedure(AUC=0.735;95%CI=0.647-0.822)with satisfactory sensitivity of 74.20%and specificity of 63.90%.Diabetes mellitus was an independent risk factor for CIN(odds ratio=2.778;95%CI=1.045-7.382;P=0.040).Conclusions:SCysC is an appropriate biomarker to predict the occurrence of CIN.Baseline sCysC before an intervention is useful to obtain a preliminary estimate of the risk of CIN.A 48-h cut-off value of sCysC of 0.99 mg/L after an endovascular procedure may help to rule out patients at lower risk of CIN.

关键词： Contrast-induced nephropathy Intra-arterial intervention Serum cystatin C Serum creatinine

新型噁唑烷酮类耐药基因optrA阳性转座子Tn6823的发现

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中国预防兽医学报 2020年第9期42卷 978-978页

作者： ZHU YAO ZHANG WAN-JIANG wang chang-zhen State Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research Institute Chinese Academy of Agricultural Sciences Harbin 150069 China Institute of Microbiology and Epizootics Centre for Infection Medicine Department of Veterinary Medicine Freie Universität Berlin Berlin Germany

噁唑烷酮类抗生素是一类新型的全合成抗菌药物,以其独特的抗菌机制对多重耐药革兰氏阳性菌,特别是耐甲氧西林金黄色葡萄球菌(MRSA)和耐万古霉素肠球菌(VRE),具有较强的抗菌活性。自2015年我国学者首次在肠球菌中发现可移动的新型噁唑烷... 详细信息

噁唑烷酮类抗生素是一类新型的全合成抗菌药物,以其独特的抗菌机制对多重耐药革兰氏阳性菌,特别是耐甲氧西林金黄色葡萄球菌(MRSA)和耐万古霉素肠球菌(VRE),具有较强的抗菌活性。自2015年我国学者首次在肠球菌中发现可移动的新型噁唑烷酮类耐药基因optrA后,其引起了国内外学者的广泛关注。目前,该基因已经在多种革兰氏阳性菌,如肠球菌、葡萄球菌和链球菌中被发现。虽然已有报道称在金黄色葡萄球菌中检测出optrA基因,但并未对其在金黄色葡萄球菌中的基因环境和传播机制进行研究。

关键词：合成抗菌药耐药基因革兰氏阳性菌肠球菌金黄色葡萄球菌抗菌机制传播机制多重耐药

Proto col Design for Output Consensus of Port-controlled Hamiltonian Multi-agent Systems

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自动化学报 2014年第3期40卷 415-422页

作者： LI chang-Sheng wang Yu-zhen School of Control Science and Engineering Shandong University Jinan 250061 China Department of Information Science and Technology Taishan College Taian 271021 China

这份报纸调查控制港口的 Hamiltonian (PCH ) 多代理人系统的产量一致问题与修理并且切换的拓扑学。第一，一个分布式的组产量一致协议经由塑造方法全球性到达稳定性和组产量一致的能量被设计。第二，一个新分布式的控制协议被使用 PCH... 详细信息

这份报纸调查控制港口的 Hamiltonian (PCH ) 多代理人系统的产量一致问题与修理并且切换的拓扑学。第一，一个分布式的组产量一致协议经由塑造方法全球性到达稳定性和组产量一致的能量被设计。第二，一个新分布式的控制协议被使用 PCH 系统的结构的性质建议。这个协议的优点是它能由构造一种虚拟邻居转变指导的图到未受指导的图。第三，一个控制协议被设计，扩大 LaSalle0s 不变性原则在联合连接的拓扑学条件下面为交换系统发展了让所有代理人当拓扑学正在切换时，到达输出一致。最后，有模拟的一些解说性的例子被提供表明在这份报纸设计的协议的有效性。

关键词：输出端口多Agent系统哈密顿设计受控控制协议多智能体系统拓扑结构

Incomplete radiofrequency ablation promotes the development of CD133+cancer stem cells in hepatocellular carcinoma cell line HepG2 via inducing SOX9 expression

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Hepatobiliary & Pancreatic Diseases International 2018年第5期17卷 416-422页

作者： Chun-wang Yuan zhen-chang wang Kai Liu Dong-Jie Liu Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Center of Interventional Oncology and Liver Diseases Beijing Youan HospitalCapital Medical UniversityBeijing 100069China Beijing Institute of Hepatology Beijing 100069China Beijing Precision Medicine and Transformation Engineering Technology Research Center of Hepatitis and Liver Cancer Beijing 100069China Department of Biochemistry and Molecular Biology Baotou Medical CollegeBaotou 014040China

Background: Cancer stem cells(CSCs) accelerate the growth of hepatocellular carcinoma(HCC) residual after incomplete radiofrequency ablation(In-RFA). The present study aimed to detect the effects of In-RFA on stemness transcription factors(STFs) expression which are important for the production and function of CSCs, and to find which STFs promote HCC stemness after In-RFA. Methods: HepG2 cells were used for in vitro and in vivo studies. Flow cytometry and sphere-formation assays were used to detect the level and function of CD133~+ CSCs in the models. PCR array and ELISA were applied to analyze the altered expression of 84 STFs in CD133~+ CSCs in two models. Specific lentiviral shRNA was used to knockdown STFs expression, followed by detecting In-RFA’s effects on the levels and function of CD133~+ CSCs. Results: In-RFA was identified to induce CD133~+ CSCs and increase their tumorigenesis ability in vitro and in vivo. The mRNA levels of 84 STFs in CD133~+ CSCs were detected by PCR array, showing that 15 and 22 STFs were up-regulated in two models, respectively. Meanwhile, the mRNA levels of seven common STFs were up-regulated in both models. ELISA assay demonstrated that only the protein of sex determining region Y-box 9(SOX9) was up-regulated in both models, the protein levels of the other 6 common STFs did not increase in both models. Finally, SOX9 was identified to play an important role in inducing, maintaining stemness and promoting tumorigenesis ability of CD133~+ CSCs in both models. Conclusion: In-RFA-induced SOX9 stimulates CD133~+ CSCs proliferation and increases their tumorigenesis ability, suggesting that SOX9 may be a good target for HCC treatment.

关键词： Hepatocellular carcinoma Radiofrequency ablation HepG2 Cancer stem cells

A homopolymolybdate-supported plate-like 2D cobalt network constructed from a new pyrazole-amide-pyridyl ligand: highly electrochemical activity in both capacitive performance and the detection of Cr(Ⅵ)

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Tungsten 2024年第2期6卷 422-427页

作者： Xiu-Li wang Yong-zhen Chen Zhi-Han chang Yu-Chun Lin Jing-Yi Ma College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Professional Technology Innovation Center of Liaoning Province for Conversion Materials of Solar Cell Jinzhou 121013China

By employing a new semi-rigid pyrazole-amide-derived bis(pyridyl)ligand[N,N'-bis(4-picolylamine)-1-hydropyrazole(4-dpap)],a new homopolymolybdate-based two-dimensional(2D)plate-like complex[Co(4-dpap)(H_(2)O)(β-Mo_(8)O_(2)6)1/2](1)has been prepared under solvothermal condition and structurally characterized.Theβ-Mo_(8)anions are fi xed between the 2D metal–organic networks[Co(4-dpap)(H_(2)O)]n 2n+via hydrogen-bonding interaction.Complex 1 possesses satisfactory specifi c capacitance of 1512.4 F·g^(−1)(current density:1 A·g^(−1))and good cycling stability(90.8%after 1000 cycles).Moreover,1 represents a promising amperometric sensor for measurement of Cr(Ⅵ)with low detection limit(0.042μmol·L^(−1))and high durability.The insertion ofβ-Mo_(8)anions between the unique 2D metal−organic networks improves the active area of polyoxometalates,which further promotes electrochemical performance.

关键词： Homopolymolybdate Metal–organic network Pyrazole-amide-derived bis(pyridyl)ligand Supercapacitor Electrochemical sensor

Aerodynamic Features of High-Speed Maglev Trains with Different Marshaling Lengths Running on a Viaduct under Crosswinds

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 975-996页

作者： Zun-Di Huang zhen-Bin Zhou Ning chang zheng-Wei Chen Su-Mei wang School of Rail Transportation Wuyi UniversityJiangmen529020China National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityHong Kong999077China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong999077China

The safety and stability of high-speed maglev trains traveling on viaducts in crosswinds critically depend on their aerodynamic characteristics.Therefore,this paper uses an improved delayed detached eddy simulation(IDDES)method to investigate the aerodynamic features of high-speed maglev trains with different marshaling lengths under crosswinds.The effects of marshaling lengths(varying from 3-car to 8-car groups)on the train’s aerodynamic performance,surface pressure,and the flow field surrounding the train were investigated using the three-dimensional unsteady compressible Navier-Stokes(N-S)equations.The results showed that the marshaling lengths had minimal influence on the aerodynamic performance of the head and middle cars.Conversely,the marshaling lengths are negatively correlated with the time-average side force coefficient(CS)and time-average lift force coefficient(Cl)of the tail car.Compared to the tail car of the 3-car groups,the CS and Cl fell by 27.77%and 18.29%,respectively,for the tail car of the 8-car groups.It is essential to pay more attention to the operational safety of the head car,as it exhibits the highest time average CS.Additionally,the mean pressure difference between the two sides of the tail car body increased with the marshaling lengths,and the side force direction on the tail car was opposite to that of the head and middle cars.Furthermore,the turbulent kinetic energy of the wake structure on the windward side quickly decreased as marshaling lengths increased.

关键词： High-speed maglev train marshaling lengths crosswinds aerodynamic features